全文获取类型
收费全文 | 8000篇 |
免费 | 566篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 136篇 |
儿科学 | 302篇 |
妇产科学 | 187篇 |
基础医学 | 1103篇 |
口腔科学 | 123篇 |
临床医学 | 720篇 |
内科学 | 1459篇 |
皮肤病学 | 97篇 |
神经病学 | 900篇 |
特种医学 | 222篇 |
外科学 | 1131篇 |
综合类 | 106篇 |
一般理论 | 15篇 |
预防医学 | 573篇 |
眼科学 | 206篇 |
药学 | 569篇 |
中国医学 | 10篇 |
肿瘤学 | 739篇 |
出版年
2023年 | 88篇 |
2022年 | 181篇 |
2021年 | 264篇 |
2020年 | 188篇 |
2019年 | 212篇 |
2018年 | 263篇 |
2017年 | 221篇 |
2016年 | 241篇 |
2015年 | 254篇 |
2014年 | 327篇 |
2013年 | 421篇 |
2012年 | 625篇 |
2011年 | 536篇 |
2010年 | 350篇 |
2009年 | 262篇 |
2008年 | 399篇 |
2007年 | 439篇 |
2006年 | 380篇 |
2005年 | 351篇 |
2004年 | 340篇 |
2003年 | 322篇 |
2002年 | 324篇 |
2001年 | 131篇 |
2000年 | 109篇 |
1999年 | 133篇 |
1998年 | 63篇 |
1997年 | 58篇 |
1996年 | 44篇 |
1995年 | 38篇 |
1994年 | 29篇 |
1993年 | 29篇 |
1992年 | 71篇 |
1991年 | 63篇 |
1990年 | 55篇 |
1989年 | 68篇 |
1988年 | 51篇 |
1987年 | 52篇 |
1986年 | 50篇 |
1985年 | 58篇 |
1984年 | 42篇 |
1983年 | 35篇 |
1982年 | 34篇 |
1981年 | 28篇 |
1979年 | 48篇 |
1978年 | 26篇 |
1977年 | 25篇 |
1976年 | 25篇 |
1975年 | 22篇 |
1973年 | 26篇 |
1972年 | 26篇 |
排序方式: 共有8598条查询结果,搜索用时 15 毫秒
41.
Randall ME Barrett RJ Spirtos NM Chalas E Homesley HD Lentz SL Hanna M 《International journal of radiation oncology, biology, physics》1996,34(1):139-147
PURPOSE: To determine outcomes and treatment toxicities in patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma treated with three courses of cisplatin-cyclophosphamide, surgical reassessment (SRA), and hyperfractionated whole abdominal irradiation (WAI). METHODS AND MATERIALS: Forty-two eligible patients entered this prospective Phase II study conducted by the Gynecologic Oncology Group (GOG). Disease characteristics were as follows: age range, 32-76 years (median 58); Stage IIIA (n = 1, 2%), IIIB (n = 2, 5%), IIIC (n = 39, 93%); histology-serous papillary (n = 21, 50%); other (n = 21, 50%); Grade 1 (n = 1, 2%); 2 (n = 14, 33%); 3 (n = 27, 54%); residual disease after initial surgery (present: n = 23, 55%; absent: n = 19, 45%). Five patients progressed while on chemotherapy, could not be effectively cytoreduced, and were not eligible for WAI. Of the remaining 37 patients, 35 received WAI. Surgical reassessment was not performed in five patients. RESULTS: Of 37 patients with known SRA status after chemotherapy, 21 (57%) were grossly positive, 4 (11%) were microscopically positive, and 12 (32%) were negative. Based on measurements recorded following initial laparotomy and surgical reassessment, progression during chemotherapy was noted in 40%, stage disease in 37%, and objective response in 23%. Toxicity during hyperfractionated WAI was limited and reversible. No patient beginning WAI failed to complete or required a significant treatment break. Following WAI, six patients underwent laparotomies for abdominal symptoms; five had recurrent disease. Five additional patients were managed conservatively for small bowel obstruction (SBO) or malabsorption, of whom three subsequently developed recurrence. Twenty-two patients having pelvic boosts were significantly more likely to require management for gastrointestinal morbidity (p = 0.0021). Considering all eligible patients, median disease-free and overall survivals were 18.5 and 39 months, respectively. Considering patients completing chemotherapy and WAI, median disease-free and overall survivals were 24 and 46 months, respectively. CONCLUSIONS: (a) Disease progression occurred within three cycles of cisplatin and cyclophosphamide chemotherapy in 40% of patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma. (b) Following limited chemotherapy, hyper-fractionated WAI was acutely well tolerated. (c) Late radiation-related toxicity was observed in only three patients (8.6%) in the absence of recurrent disease. Late gastrointestinal morbidity was significantly associated with the administration of a pelvic radiotherapy (RT) boost. (d) Short duration chemotherapy followed by SRA and hyperfractionated WAI without a pelvic boost is a promising management option for patients with optimal Stage III ovarian cancer. A Phase III trial will be necessary to determine how this treatment strategy compares with chemotherapy or RT alone in this patient population. 相似文献
42.
Fernando Santos James C. M. Chan James D. Hanna Kazuhiko Niimi Richard J. Krieg Jr Martha D. Wellons 《Pediatric nephrology (Berlin, Germany)》1992,6(3):262-266
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities. 相似文献
43.
44.
Wayne L. Furman John H. Rodman Margaret E. Tonda Xiaolong Luo Bettye Arnold Neyssa Marina Leslie Garrison Roberta Hanna Charles B. Pratt William H. Meyer 《Cancer chemotherapy and pharmacology》1997,41(3):229-236
A hemopoietin with the ability to accelerate both platelet and granulocyte recovery after intensive chemotherapy would have
great clinical utility. The recombinant fusion protein composed of human granulocyte-macrophage colony-stimulating factor
and interleukin-3 (PIXY321), showed some promise in early adult trials. However, studies for pediatric patients are limited,
and there are no systematic data on the pharmacokinetics of PIXY321 given over prolonged periods at current dosage levels.
Purpose: To determine the safety, clinical effects and plasma concentrations of increasing doses of PIXY321 in children treated with
myelosuppressive chemotherapy. Methods: A total of 39 children with relapsed or high-risk solid tumors were enrolled in this phase I/II study. PIXY321 was administered
once or twice daily by subcutaneous injection in total doses of 500 to 1000 μg/m2 per day for 14 days after each course of chemotherapy with ifosfamide, carboplatin, and etoposide (ICE). Pharmacokinetic
studies were performed on day 1 of the first course in 33 patients and repeated on day 14 in 13 patients (once-daily schedule
only). Results: Although mild local skin reactions and fever were frequent, no dose-limiting toxicity was identified at the maximum dose
studied (1000 μg/m2 per day). There were no statistically significant differences in chemotherapy-induced hematologic toxicity with increasing
doses of PIXY321 or with twice-daily vs once-daily dosing. On day 1, the median PIXY321 clearance was 657 ml/min per m2 (range 77–1804 ml/min per m2) and the median half-life was 3.7 h (range 2.1–20.8 h). On day 14, clearance increased in all patients studied (median increase
63%), with a corresponding decrease in the median 12-h concentration (from 1.2 to 0.25 ng/ml). Maximum concentrations were
<1 ng/ml in 81% of patients, and only two patients had maximum plasma concentrations equivalent to those required for consistent
activity in vitro. Conclusions: The recombinant fusion protein PIXY321 proved safe in children treated with myelosuppressive ICE chemotherapy but had no
demonstrable clinical benefits. The pharmacokinetic studies suggest that the observed lack of hematologic benefit may be explained
by low plasma concentrations resulting from increased clearance with prolonged administration. Moreover, the significant increase
in PIXY321 systemic clearance in the absence of increased circulating myeloid cells suggests that the upregulation of either
extravascular compartment hematopoietic progenitor cells or nonhematopoietic cells may play an important role in controlling
circulating concentrations of this unique cytokine. These findings highlight the importance of a thorough assessment of the
systemic disposition of cytokines when determining the dose and schedule necessary to achieve clinical activity in patients.
Received: 29 January 1997 / Accepted: 9 May 1997 相似文献
45.
Clinical, electrophysiological, and molecular genetic studies in a new family with paramyotonia congenita 总被引:1,自引:0,他引:1 下载免费PDF全文
Davies NP Eunson LH Gregory RP Mills KR Morrison PJ Hanna MG 《Journal of neurology, neurosurgery, and psychiatry》2000,68(4):504-507
OBJECTIVES: To characterise the clinical and electrophysiological features and to determine the molecular genetic basis of pure paramyotonia congenita in a previously unreported large Irish kindred. METHODS: Clinical and neurophysiological examination was performed on three of the five affected family members. Five unaffected and three affected members of the family were available for genetic testing. Direct sequence analysis of the SCN4A gene on chromosome 17q, was performed on the proband's DNA. Restriction fragment length polymorphism (RFLP) analysis was used to screen other family members and control chromosomes for the SCN4A mutation identified. RESULTS: Each affected member had clinical and examination features consistent with pure paramyotonia congenita. Electrophysiological studies disclosed a 78% drop in compound muscle action potential (CMAP) amplitude on cooling to 20 degrees C. DNA sequence analysis identified a heterozygous point mutation G4367A in exon 24 of the SCN4A gene which segregated with paramyotonia and was absent in 200 control chromosomes. The mutation is predicted to result in a radical amino acid substitution at a highly conserved position within the voltage sensing fourth transmembrane segment of the fourth repeated domain of the sodium channel. CONCLUSIONS: The G4367A mutation is likely to be pathogenic and it associates with a pure paramyotonia phenotype. In keeping with other paramyotonia mutations in this region of the skeletal muscle sodium channel, it is predicted that this mutation will impair voltage sensing or sodium channel fast inactivation in a temperature dependent fashion. This study provides further evidence that exon 24 in SCN4A is a hot spot for paramyotonia mutations and this has implications for a DNA based diagnostic service. 相似文献
46.
Physical activity combined with massage improves bone mineralization in premature infants: a randomized trial. 总被引:5,自引:0,他引:5
Hany Aly Mohamed F Moustafa Sahar M Hassanein An N Massaro Hanna A Amer Kantilal Patel 《Journal of perinatology》2004,24(5):305-309
BACKGROUND: Osteopenia of prematurity is a known source for morbidity in preterm infants. Premature infants have shown favorable outcomes in response to massage and physical activity. Whether such intervention can stimulate bone formation or decrease bone resorption is yet to be determined. OBJECTIVE: To test the hypothesis that massage combined with physical activity can stimulate bone formation and ameliorate bone resorption in premature infants. DESIGN/METHODS: A prospective double-blinded randomized trial was conducted at the Neonatal Intensive Care Unit of Ain Shams University in Cairo, Egypt. Thirty preterm infants (28 to 35 weeks' gestation) were randomly assigned to either control group (Group I, n=15) or intervention group (Group II, n=15). Infants in the intervention group received a daily protocol of combined massage and physical activity. Serum type I collagen C-terminal propeptide (PICP) and urinary pyridinoline crosslinks of collagen (Pyd) were used as indices for bone formation and resorption, respectively. PICP and Pyd were measured at enrollment and at discharge for all subjects. t-Test, ANOVA and linear regression analysis were used for statistical analyses. RESULTS: There was no difference between groups I and II in gestational age (32.1+/-1.8 vs 31.5+/-1.4 weeks) or birth weight (1.429+/-0.148 vs 1.467+/-0.132 g). In the control group, serum PICP decreased over time from 82.3+/-8.5 to 68.78+/-14.6 (p<0.01), while urinary Pyd increased from 447.7+/-282.8 to 744.9+/-373.6 (p<0.01) indicating decreased bone formation and increased bone resorption, respectively. In the intervention group, serum PICP increased over time from 62.5+/-13.8 to 73.84+/-12.9 (p<0.01). Urinary Pyd also increased over time from 445.7+/-266.5 to 716.8+/-301.8 (p<0.01). In a linear regression model including gestational age and intervention, serum PICP increased significantly in the intervention group (regression coefficient 18.8+/-4.6, p=0.0001) while urinary Pyd did not differ between groups (regression coefficient=5.6+/-114.3, p=0.961). CONCLUSIONS: A combined massage and physical activity protocol improved bone formation (PICP) but did not affect bone resorption (Pyd). Pyd increased over time in both groups, possibly due to continuous bone resorption and Ca mobilization. 相似文献
47.
48.
49.
50.
The impact of geographic unit of analysis on socioeconomic inequalities in cancer survival and distant summary stage – a population‐based study 下载免费PDF全文
Hanna E. Tervonen Stephen Morrell Sanchia Aranda David Roder Hui You Theo Niyonsenga Richard Walton Deborah Baker David Currow 《Australian and New Zealand journal of public health》2017,41(2):130-136
Objective: When using area‐level disadvantage measures, size of geographic unit can have major effects on recorded socioeconomic cancer disparities. This study examined the extent of changes in recorded socioeconomic inequalities in cancer survival and distant stage when the measure of socioeconomic disadvantage was based on smaller Census Collection Districts (CDs) instead of Statistical Local Areas (SLAs). Methods: Population‐based New South Wales Cancer Registry data were used to identify cases diagnosed with primary invasive cancer in 2000–2008 (n=264,236). Logistic regression and competing risk regression modelling were performed to examine socioeconomic differences in odds of distant stage and hazard of cancer death for all sites combined and separately for breast, prostate, colorectal and lung cancers. Results: For all sites collectively, associations between socioeconomic disadvantage and cancer survival and distant stage were stronger when the CD‐based socioeconomic disadvantage measure was used compared with the SLA‐based measure. The CD‐based measure showed a more consistent socioeconomic gradient with a linear upward trend of risk of cancer death/distant stage with increasing socioeconomic disadvantage. Site‐specific analyses provided similar findings for the risk of death but less consistent results for the likelihood of distant stage. Conclusions: The use of socioeconomic disadvantage measure based on the smallest available spatial unit should be encouraged in the future. Implications for public health: Disadvantage measures based on small spatial units can more accurately identify socioeconomic cancer disparities to inform priority settings in service planning. 相似文献